Apparatus for making spark plugs



May 22, w23.

Y M4555@ D F. PYLE ET AL APPARATUS FOR MAKING SPARK PLUGS Filed oct. 27, 1921 3 Sheets-sheet 1 Y I f May 22, w23. Mss l D F. PYLE ET AL APPARATUS FOR MAKING SPARK PLUGS Filed Ot. 27 1921 3 Sheets-Sheet 2 D F. PYLE ET AL.

APPARATUS Fon MAKING SPARK PLUGS 'May i923.'

Filed oct. 27, 1921 3 sheets-sheet s Il n gglllmm www att ay 22, 1923.

D FRANKLIN PYLE, OF WASHINGTON, DISTRICT F CGLUMBIA, AND J i# "its i l APPARATUS FOR MAKING SPARK PLUGS.

Application led October 27, 1921. Serial No. 510,754.

To allfwhom z't may concern.'

Be it known that D FRANKLIN'PYLE and JAMES Arnorcneor citizens of the United' States, residing at ashington, District of o Columbia, and Catonsville, State of Mary- 1 land, respectively, have invented certain new and useful Improvements in Apparatus for Making Spark Plugs, of which the vfollowing is a specification. R0 l This invention relates to an apparatus for manufacturing spark plugs.

The spark plug for which the apparatus is designed to manufacture is one comprising a metallic shell threaded in the usual il@ manner for insertion into the wall of the eX- plosion chamber of explosive engines, and in which there is a core ofinsulating material such as glass, in which there is embedded in its completed form, the positive pole or electrode. y

In the manufacture of spark plugs of this character, it is essential thatvthe shell of the plug be rigidly and positively supported at certain stages in the operations incident to its manufacture, as to both lateral and vertical movement, it bein desirable to prevent lateral movement so t at the electrode or the ,parts formin the central pole or electrode be accurate y centered in the insulat- 8@ ing material withln the shell, and also in relation to the outer extremities of the shell itself, and held 'positively against vertical movement so that the die carrying plunger, which forms an essential part of the apparatus, will not lift the plu from its seat when said plunger recedes a ter having compressed the insulating material into .the shell and inserted therein the central pole or electrode or a part thereof.

The object of the invention is to improve the construction of machines or molds of this character generally, and particularly to provide a construction wherein the metallic shell of the plug is braced and held rigidly in proper position in the mold during the operations of filling said shell with insulat-A in material, and embedding in such materlal the electrode, and to provide a novel and eiiicient'means for holding the shell and its contained insulator and electrode in rm and positive position. in the mold upon lthe recession of the die carrying plunger.

y,tion of the ejector.

A further object of the yinvention is to provide a construction wherein the plug is readily and conveniently ejected from the base of the mold.

Other objects and advantages of the in- Vention will, in the course of the following description, become apparent to those skilled in the art to which this invention apper- 30 tains, and the points of novelty will be set forth in the claims.

In carrying out the invention we provide a table or rest for the'mold which contains parts which cooperate with the mold during` @5 the various operations incident to the manufacture of the plug, and may accordingly /form particular elements in the combinations of mechanisms about to be described.

/In the drawings illustrating the invention: Fig. l is an edge diagrammatic view of a table which may be employed.

Fig. 2 is a plan view, diagrammatic, of a portion of the table.

Fig. 3 is a central section of the lower part of the mold, there bein in place in the mold, `in section, the she of a spark plug, and before the same has been filled with molten insulating materialf 5@ Fig. 4 is a similar section of a portion of the lower part of the mold in proper relative position to a fragment of the lower end of the plunger, which is also in section, there being also shown in place in the mold, the 35 shell of the plug showing the same filled with insulating material, but before fusing pressure has been applied.

Fig. 5 is a central'section of the mold showing in proper relation thereto the plunger, and the means for holding the shell in place during the upward-movement of the, plunger, there being shown a completed plug in its proper relative position -to the mol and plunger parts, the positions of said parts being those which they occupy just before the plunger and die caried thereby recede, or are withdrawn. Fig/6 is a top plan view of the upper por@ E.

, um Fig. 7 is a group view, side elevation and bottom section, of the gripper for initially holding the central electrode in the end of f theplunger. t

Fig. 8 is a central sectional view of lthe mold, and a portion of the table upon which l it is operated, the section of the table being taken on that point where is located one of the elements of' the ejector.

Fig. 9 is a top plan view of the mold.

Referring to the drawings, the numeral 1 designates thetable'upon which vthe mold may be operated, of which, and the parts carried thereby, or more intimately associated therewith, more will be said presently.

The numeral 2 designates the base of the mold, as a whole, which base comprises a central portion of substantial build, but for purposes of lightness and ease of handling, ,the remaining part of the base is of comparatively light construction. It is provided with a bottom flange 2 of considerable width, and vat its rear end there is a standard 3 provided with an ope-ning 4 for the passage of a bolt which extends through ears 5 of a comparatively heavy lid 6,

, whereby the lid is pivotally secured to the standard so that the same may be brought 'to horizontal position, or raised out of the way and tilted back as shown in dotted lines in Fig. 5, and in full lines in Fig. 8. The lid is provided with a heel 7 which engages the `shoulder 8 on the standard to prevent the lid from moving -too far back when lifted. The lid is further provided cen-i trally with an aperture 9 formed with bevelled inner periphery 10 to receive the die carried by the plunger, and an oppositely bevelled lower portion 11, which receives and conforms to the upper edge 12 of the spark plug shell 13. The shell of the plug, as is usual, is provided with the shoulder 14, and for engagement with this shoulder we provide an annular seat 15 which is secured by means of screws 16 to the upper ends of circularly arranged posts 17, the lower ends of the posts being rigidly secured by short screws 18 to the disk 19, fitted and adapted for vertical movement in circular yrecess 20 made in the bottom of the mold.

it may be adjusted vertically lfor the purposeof forming a cavity of greater or less depth in the molten material when it is poured into the shell, it being obvious that there is sufficient space within the recess 20 for such vertical adjustments, without interfering in any vappreciable way with the proper ejectment of the finished plug.

Seated in a bore 24 in a boss 25 on the front of the base of the mold is the inner end of handle 26 which isheld in place by set screw 27, the outer end of the handle being provided with a suitable grip portion by which the whole machine may be readily moved from place to place upon the table 17 or any other suitable support.

The numeral 28 designates so much of a standard of a press as is necessary to vshoe7 its relation to the mold, in one of the stages the shell of the spark plug in the molding operation, and to prevent upward movement of the plug when the plunger recedes, or is being withdrawn. The lower end Aof the plunger 30 is provided with a threaded recess 34 which receives the threaded boss 35 of the die 36, which die is formed with a centrally circular boss 37 designed to form the depression 38 in the top of the glass insulating material 39 within the'shell of the spark plug, the outer edge of the bottom of the die extending in its lowest position to `the bottom part of the bevelled portion 10 of the lid, as shown, and to the upper edge of the bevelled portion 16 of the lid, and the die is undercut as indicated at 40, thus forming an annular space when the die is down to receive any very small particles of the insulating material that may, under pressure, during the operation of the molding; be in excess of that necessary to suffi-v Ciently fill the shell. The die 36 is provided with a bore 41 which receives the gripper 42 which is formed with a head 43, which fits snugly in the top of the recess 34, and is held therein bythe boss of the die, as shown. This gripper is provided with a plurality of resilient fingers 44 designed to grip and hold temporarily, the upper portion of the central electrode which pole or electrode is bifurcated at its lower end as indicated at b for the reception and final retention of the reduced endl c of the central electrode. v

Referring particularly to Fig. 8, the numeral 45 designates a leverwhose end terminates shortly beyond the edge of the table in a handle46, and the opposite end of the lever is pivoted at 47 between two ears 48 integral with the table. Preferably about midway of its width, the table is provided with a vcylindrical aperture 49 through which extends the lower member 50 of the ejector, which member is provided at its up'- per end with a broadened portion 51, which engages centrally the under face of the disk 19. the table being recessed as indicated at 52 to receive the head 51 when the member 50 is in its down or lowest position. The

lower end of the member 50 is pivoted as which is poured into the shell, the glass or other molten insulating material. After the' `ulation of the lever will cause the disk 19 and parts carried thereby to be raised at will to the position shown in Fig. 8 for the purpose of ej ecting or knocking oli' the completed plug.

Reverting to the table illustrated in the diagrammatic views Figures 1 and 2, the letter e designates a plurality of stops which cooperate with` stops f, the stops being rouped together at intervals on the table; t e front stops e serve to limit the forward movement of the mold when the same is pulled within the stops, and the rear stops are provided with anges, as shown, which slightly overlap the flange 2', the latter stops preventing the lateral movement of the mold from any ofits predetermined positions on the table.

The operation of the apparatus above described is as follows:

- The lid 6 is thrown back out of the way,

and the shell'13, after having been previously heated, is inserted in the pocket 21` inthe base of lthe mold, with the annular shoulder 14 resting upon the inner upper edges of annular seat l5, with the upper part of the cavity-forming die extending into the shell, as shown in Fig, 3. There is inserted in the recess in 4thecavity-forming die, the reduced lower portion c of the central electrode, which portion is, it will be understood, temporarily held in t is portion of the die preparatory to its union with the upper portion ofthe electrode a. The lid 6 which is quite heavy, is then brought down on the upper edge of the shell, which byv reason of the conformingy bevelled surfaces of the lower part of the aperture 9 centers the shell properly upon its rest. rlhe upper part of the electrode a is then inserted into the gripper in the die\.\36, wherein it is firmly, but temporarily held, the electrode having, like the shell and the lower part c of the electrode, been previously heated to a deg'ree` suiiicient to bring about a very tight union, between the upper and lower parts of the electrode, and a fusing of the molten insulating material upon the exposed parts of said electrode. The mold is then moved upon the table to a position under a suitable filler, (not shown) from the nozzle of shell receives an adequate amount of material, the mold is moved to the position determined by the appropriate stops, wherein it may be directly below the die` of the plunger 30, and upon depression of the plunger, the die will enter the recess in the lid 6 and apply the necessary pressure to the molten material, and depress or form in said material, the proper pre-determined configurations, in the present case, the depression 38, which depression forms the seat in which the lower end of the insulating sleeve rests in the finishing of the plug. rlhis downward movement of the plunger in# serts the upper part of the electrode a, centrally in the molten material within the trode a which remains embedded in the insulating material in the shell, and inthe upward movement of the plunger the stop 33 in engagement with the lid 6 steadies and holds the shell, and its then contained parts,

' against the tendencyto follow the plunger.;

The mold is then moved to another point on the table pre-determined by the appropriate stops, and this last point is the one immediately above the ejector member 50, so that when the handle to which the member is pivoted is raised, it will lift the disk 19 and parts C'carried thereby, including the annular seat 15 upon which rests the shell 13, land inv the upward movement. the shell strips the cavity-forming die from the lower portion of the electrode (see F ig. 8), so that the plug may be readily removed for the final necessary treatments, which in`most cases, comprehendsthe provision of an insulating sleeve for encasing the upper part of the electrode, and theprovision of clamp screws, washers, etc. for the convenient reception of the usual electrical terminals.

We do not desire it to be understood as limiting ourselves te the use of any particular kind of press or machine for actuating the upper die, and it is obvious that wel may use any suitable machine for this purpose, it only being essential that there be a plunger which carries the die we have described, and the reciprocatory movement or stroke of the plunger may be given to it by any suitable means, as for instance, a hand-lever, orby mechanically or electrically operated device,

.nor do we desire to limit urselves to the particular form of table shown and described, and may vary the same within the spirit ofthe invention so long as there are an aperture therein, said lid adapted to rest l llO upon and hold in place said article, and said aperture serving for the passage ot' the inaterial to be filled into the article, and also as an entrance opening for a suit-able plun- .ger, a pressure applying plunger adapte'd to apply pressure to the material with which the ai'ticle is filled, and means for actuating said plunger.

2. A mold comprising a base, an ejector in said base, comprising a plurality of posts whose upper ends are (onnected by an annulus which foi-nis 'a seat for the article upon which the mold is adapted to operate, means connecting the lower ends of said posts 'whereby they, and the parts carried thereby, are moved vertically, a lid pivoted upon the base and having an aperture therein for the passage of the material to be filled in'to the article, and also for the entry of a pressure applying plunger, a pressure applying plunger and means for actuating the same.

3. A mold comprising a` base, an ejector in said base formed in part ot' an annulus forming a seat for the article upon which the mold is adapted to operate, a cavityforming die Within the ejector for the purpose set forth, a lid pivoted above the seat and having an aperture therein for the passage of the material tovbe Iilled into the article, and also for the entry ot' the plunger for applying pressure to the filler of said article, said lid being -adapted to prevent movement of the article both vertically and laterally.

4. A n'iold comprising a body having aV flange around its lower edge adapted to cooperate with suitable stops upon a suitable support to hold the mold in a detinitepredetermined position, an ejector in said mold comprising in part an annular seat for the article upon which the mold is adapted to operate, a. cavity-forming die within the annular seat, a lid above said seat adapted to rest upon the article toA simultaneously prevent its movement in vertical or lateral direction, said lid having an aperture therein for the passa e of the filler of the article, and also for t ie entry of a pressure applying plunger that operates upon the filler, means i'or actuating the plunger, and means for actuating theejector for the purposes set' forth.

5. A mold comprising a base having a'seat for the article upon which the mold is adapted to-operatc, a lid above the seat and engaging the article Ito prevent either vertical or lateral movement of said article, said lid having an aperture therein Whose sides are inwardly bevelled, a plunger, a die carried by said plunger, the plunger being provided `With an undercut annular portion, Which when the die is in theaperture in the lid forms an annular pocket for the over'lou7 of excessive portions for the ller, and means for actuating said plunger. l

6. In a mold ofthe character described, in combination, a suitable table. having suitable stops thereon which predetermine the positions of the mold on said table, an ejector element carried bysaid table, a mold comirisino' a base. an e'ectoi in said base a-da t-.

ed to looperate with the ejector element of the table` said last mentioned ejector elefiller of said article in the molding operation,

and means for operating said plunger.

In testimony whereof `We affix our signatures in presence of two Witnesses.

D FRANKLIN PYLE. JAMES ANDER-SON.v

Witnesses JNO. L. CRAWFORD, M. A. AHERN. 

